Expansion-bolt.



R. R; KNOX.

EXPANSION BOLT.

APPLICATION FILED 00114, 1913 1 ,1 1 0,797. Patented Sept. 15, 1914.

l l/i THE NORRIS PETERS co.. PHOYO LlrHa, WASHINGTON. u 4:

1 ginonnn'r Rt-KNOX, or sAn rnnndrsco; onn ronixiia.

. EXPANSION-BOLT. v I i i To m it armara;-

Beit known that I, Bonnier R. Knox, a citizen of'the United States, residing in the city and countyof San Francisco and State of California, have in'ventednew, and useful Improvements in Expansion-Bolts, of which the following is a specification; t v

Th's invent'o-n relates to an expansion bolt.

' It is theobject of this invention to provide a boltjwhich'is adapted to bednserted in perforations formed in the materials to-be bolted together and then be expanded so as to prevent its being withdrawn. I

A further object is to provide an expansion bolt of the'above character,wh'ich is, simple in construction, economical 1n manu-1 facture, efi'iclent, strong and durable, andwhich is applicable foruse in concreteand other masonry construction as well as in metal and timber constructions.v t g The invention consists of theparts and the construction and combinationfof parts as hereinafter more fully described and claimed,

having'reference to the accompanying draw- 1 v \surface C of material; in which theshank A ings, in which, I t

Figure '1" is a longitudlnal section of the preferred form of the invention on the line 22 of Fig. 2. Fig. 2 is a cross section-"of same on the line 1+1 of Fig." 1. Fig.3 is a perspective lview of the expander and wedge.

Fig. 4: is a View in elevation of modified" form of the invention; tion of Fig. 4:. Fig. 6 is a section of a fur- Fig. 5 is a cross secther modification. t

In the drawings, A represents the expander, which is here shown of suitable cross section, and is threaded a suitabledistance,

as at 2, to receive a complementary part 3.

The lnventlon resldes in forming longitudinally disposed grooves l on the shank A; these grooves 4:. extending any suitable,

, length thereon, preferably from one end to a point near the end of the bolt shank forming shoulders 4 and may be separated by corners or longitudinal ribs 4?, Fig. 3. The

bottoms of the grooves 4: are inclined from their outer ends toward the center or axial line ofthe expanden as indicated at 5 in Fig. 1, at any suitable degree of inclination. .Slidably mounted in each groove 4: and removable therefrom is a wedge block 6, the

bottom of which block is inclined to correspond to the inclination of the bottoms 5 of the grooves 4. Formed on the outer curved, face of the block 6 is'a series of teeth 7, the

.uppei'. edges o -rpoints of which teeth are approximately in alinement with the periphery of the shank A, when the block 6 is disposed at its innermost position in the slots 4:, as

oni'an expander A may be varied according tothe size and the purpose for which it is to provide a pair ofopposed slots 4 and blocks 6, as shown in Figlw6.

'. shown in Fig.1, although the foremost tooth v mayproject-a short distance beyond the peripheral face of the shank A. Thenumber of slots ,4; and toothed blocks "6 employed be applied; a single slot 4 andblock 6 being employed, as shown in Fig. 4-, in some instances; while in others it is desirable to P Lln the application ofthefinvention i i forationB lisformed in the partsto be joined together, of a diameter. approximately equal j to that of'the; shank Thehead endof the, shank A is then; inserted in the perforation so asto dispose theserrated or toothed block 6 ,therein. The actuating part 3 is then screwed on thevthreaded portion of the eXpandenA soas toibearagainst a part .8,

which is adapteditobear against the outer is mounted- By turning the part-or screw 3 the shank A' will be caused to advance, which "actionicausesthe'wedges 6 to move radially, as indicatedin dotted lines in Fig. 4, in such aima'nne'r as to cause'tlie teeth 7Ythereon to dig into the wall of the perforation B in which the. bolt is disposed. The outward movement of the wedgesfiat right angles to theexpander A is caused by the wedge-like action of the inclined bottoms 5 of the slots 4- Thesetting of the teeth may be accomplished by moving the shank A toward the wall of the'perforation B in such manner as to press the points, or one tooth as 7, against the surface of the perforation; the point of the tooth 7 projecting beyond the outer circumference ofthe shankA admitting ofits being quickly engaged.

From the foregoing it will beseen that the more the part 3 is tightened, the tighter; the toothed blocks 6 will be engaged with.

the material surrounding the expander and effectually prevent the body A being removed.

It is obvious that as manyteeth or serrations 7 maybe formed on the blocks Gas desired; the fewer the teeth and the shorter the block, the-greaterthe range of the outward movement of the blocks 6.

The expander shown in Figs, 1, 2 and 3 is of 'poiygonzd cross section With four," inclined channels terminating at their shah 10W ends at the shoidd'ersd", which prevent the Wedges over-riding. In order toclamp the Wedges 6 temporarily While being ad.-

j usted the hole B; springs 10 are secured f at the shoulder 4 and] oyerlapthe Wedges which'have curved outer teeth e'dges, -these being di videdvat 11 for the spring end.*'

" "In FigJ- JCtheeXpander is prbvided with" external "threadsend inn; 3, hile Fig.1 shotvs'at form yvithi'nternal threads; 3

*Having thus described inyention what I elaim and d sir to semis byfLetters An expansionflbol't 'cbinprisihg ex pander Withinclinedsea-ts, wed e mined in said seats against side fir 'loyeinent slidable thereon, means for I adyanci'ngth'e expander axially to s'p'readthe wed 'es Wheh engaged by a contiguous fiXed surface, and

' -.n1ne2tns2ittachd to the expander for terfnpo-r in s'ziid seats- "againstsidegtnovenient tnd slidablethereommn eans "for adyanclng the p nder wi h; iiiclinediseztts fl expander axiallyto'fspr e ctd thefived es when engaged by contiguo s gfixu I Sm? rrieztns attached to? the" ex nder for ltemporv rarily holding th'Wedge's upon'the egg pander i free to overlap the w gge holding the Wedges, upon the eX,-

w i n v my an y WltI lBSSBS v ,saldl'atter ineanscoinp'r smg springs in said seats against lside movement and slidable thereon, meansfor advancing the pander,

expander axially to spred dithe wedgeswhen engagedby: a contiguousffixed surface,xand- 7 means attached to the expander for tempo-z rarily holding the Wedges lup'o'n -thei eX- said gwjedges- "haying seats for springs."

4:. An expansion boltgiconiprisingua body part With inclined 'sesits' 'and rner, ribs f ming side Walls" of the seats 2Lp1ura1'ity of Wedges with arcuat'e' surfaces; subtitnt ally aggre atmg a circle encoinpgt mgthe v body partfand being separatedjby the; corner Wesliing ton, 1)., 0.? I

with ihchndbottoms hdjhaving; shoulders at theshaillow ends of, the groo'v ribs, andinezt'n'sfor advanciiigthe body pert. c A e P si n. ltoki ld 'ie w pr ing an expander having longitudinally ex tending grooyestherein, saidgroovesfor'ined;

. r iQY-"-- able tapered blocks slidab'le in said. grooves;-

series" oif:"teet1 1 i orlnedfon'the pper faces of said blocks with their-outer ends termi 4 hating: on a level with the outer k periphery of the expander, locldng teeth "formed, on the-block with their outer ends projecting beyond the outer ends of the otherflteeth,

threads formed onfithe expa nderendfla coin p m n e y pe fi ted". one t thread In testimony ha ve hereunto set? the'presence of 'cribing Witnesse sE v p p n JOHN H IHERRING, .l a

Goinn i issioner of iatentsll 

